1. Field of the Invention
The present invention relates to a substrate for mounting a device and a method for producing the same, a semiconductor module and a method for producing the same, and a portable apparatus provided with the same.
2. Description of the Related Art
Amid the acceleration of high performance of portable electronic apparatuses such as portable phone, PDA, DVC, and DSC, in order to be accepted in the market, it is essential that such products are miniaturized and reduced in their weight. Hence, there is also a demand for miniaturization of semiconductor modules such as multi-chip module (MCM) or the like used in these electronic apparatuses. With respect to the demand, a semiconductor device is known in which an active device such as a semiconductor chip, and a passive device such as a capacitor, are covered by an insulating layer formed on a substrate, and the active device and the passive device are connected to a wiring on the insulating layer via the insulating layer. In recent years, with miniaturization and high performance of electronic apparatuses, there is a demand for further miniaturization of semiconductor devices used in the electronic apparatuses. With miniaturization of semiconductor devices, it is essential to narrow a pitch between electrodes for being implemented on a printed wiring board. As a surface-mounting method of a semiconductor device, a flip-chip mounting method is known in which a solder bump is formed on an electrode of the semiconductor device, and the solder bump and an electrode pad of a printed wiring board are soldered. However, in the flip-chip mounting method, there are limitations in narrowing the pitch between electrodes, because of restrictions resulting from the size of the solder bump itself and occurrence of bridges while soldering, or the like. As a structure for overcoming these restrictions, a structure is known in which a projected structure formed on a substrate is used as an electrode or a via, and a semiconductor device is mounted on the substrate via an insulating resin such as an epoxy resin, such that an electrode of the semiconductor device is connected to the projected structure.
However, in the conventional semiconductor devices, there are problems that miniaturization of a semiconductor module is suppressed and the number of the production processes is increased, because a passive device such as a capacitor or the like is mounted on a silicon substrate as a separate part. Further, in the structure in which a wiring layer of a substrate for mounting a device and a semiconductor device are made into one body via an insulating resin, such that a projected structure provided on the wiring layer and an electrode of the semiconductor device are connected, adhesion between the insulating resin and the semiconductor device is not high. Therefore, there is a fear that the insulating resin could peel from the semiconductor device by a thermal stress generated due to, for example, a change in temperature of the environment. In particular, in the case where an interval between the projected structures penetrating the insulating resin is large, as is in the conventional structure stated above, the insulating resin is easy to peel from the semiconductor device between the projected structures. And, in the case where the insulating resin peels from the semiconductor device, adhesion between the projected structure and the semiconductor device is decreased; and as a result, there is a fear that the connection reliability between the projected structure and the semiconductor device is decreased.